errett



April 29, 1941. s, .1, ERRETT CUTTING AND WELDING TORCH Filed Aug. 22, 1938 uv/av TUR SANFORD J. 22am Patented Apr. 29, 1941 UNITED STATES PATENT OFFICE will CUTTING AND WELDING T0301! Sanford 1. Brett. Portland. Oreg. Application August 22, 1938, Serial No. 326,103

SClaiml- Thls invention relates to improvements in oxyacetylene or oxyhydrogen cutting and welding torches, and has particular reierence to an improved torch head. and to a new and improved means for preventing combustible mixtures of oxygen and acetylene gases in the passages of the torch.

Primarily, it is an object of the invention to provide a construction tor a cutting torch which precludes the inter-mixing of oxygen and acetylene gases to a point of combustibility within the cs the torch.

It is also an object of the invention to provide a new and improved means for sealing the possagesiorthehighpressurecxyseni'romthe passages to: the low pressure gases.

Itisarurtherobimtoitheinvention tomvide ior sealing thepaseageror thehigh pressure oxygen from the passages for the low pressure gasesbyssealwhichwiilteiorexpension and/or contraction of the parts due to variations in tem perature. It is a further object of the invention to provideatorch headhavllischamhersprovidinl pockets for excess volumes oi unmixed gases in the low pressure gas lines.

It is a iurther object 0! the invention to provide in a cutting torch a construction the new or highpressure oxygenservestoinsulnte the passages for the low pressure gases from the heat created by the torch name.

It is a further object of the invention to provide means for cleaning the passages in a torch head without dismantling the torch.

To the accomplishment oi the recited objects and others coordinate therewith, the preferred embodiment oi the invention resides in the con struction and arrangement of parts hereinaiter described, illustrated in the accompanying drawing, and embraced within the scope of the appended claims.

In the drawing:

Figure 1 is a side elevation, partly in section, oi a torch head and cutting tip embodying the principles of the present invention.

Figure 2 is a cross sectional elevation 01 the torch head, taken on the line 2-1 of Figure 1.

Figure 3 is an enlarged section 0! the torch head taken on the line 3-3 of Figure 1.

Figure 4 is an end view of the cutting tip.

Figure 5 is a sectional elevation oi the torch head taken on the line 5--S of Figure 2.

Figure 6 is a perspective view 0! a cutting tip adapted for use with applicants torch head.

The illustrated embodiment of the invention as 2 and iorms eomprisesatorchhead i having acutting tip 2 disposed in abutting relation with the iorward The tip shown is provided on its inner end with a central extension I which is I provided in throughapassage thetorchheedstitscentenandthrougha centrally or the tip. Thepasthe tip extends through the extension causedtoregistcrwiththepassagelin headwhentheextensiontisinserted to sockettlinannularchamberlis formed about the xtension, 3 between the inner endoithetipandtheendoithetorchhead.

mately mixed during their e through the tip. it ferrule ll covers the inner end or the tip the outer wall of the chamber I.

Applicant seals the how of high pressure oxygen from the mixture of low pressure gases in thechamberlbyhrazingtheextensionI oi the tip into the socket i. In the construction illustrated, the juncture of the tip extension I and the socket l is the only joint within the torch at which leakage oi the high pressure gases might occur, and applicant precludes such leakage by brazing this joint. An advantage of this construction resides in the fact that a brazed joint will wholly compensate for expansion. or contraction oi the parts due to variations in temperature. such as may occur when the torch becomes heated, as when used for cutting bolts and rivets on marine work and the like. On the other hand, a joint which is dependent upon screw threads to maintain a seal will loosen when the torch becomes heated, and the consequent admixture oi! gases which results from leakage of oxygen from the high pressure line into the mixing chamber for the low pressure gases, will cause the flame to strike back along the gas passages of the torch, resulting in dangerous explosions therewithin.

In addition to brazing the tip to the torch head in such manner as to provide a brazed seal between the flow of high pressure oxygen and the mixing chamber for the low pressure gases, the tip also is fastened to the torch head by the brazed joints ll-H which secure one end of the ferrule HI to the tip and the other end of the ferrule to the torch head. These brazed joints form impermeable seals to preclude leakage of the mixed gases from the chamber I to the atmosphere. The tip may be removed from the torch head by heating the brazed joints sufliciently to melt the solder.

The torch head I comprises a cylindrical body wherein is embodied the respective passages through which the separate gases are conducted to the tip 2. A boss or shank I2 on the torch head serves as a connecting means for the gas supply lines (not shown) which are insertible into the shank i2 in registration with, respectively, the intake port l3 for the high pressure oxygen, the intake port H for the acetylene or other fuel gas, and the intake port l5 for the low pressure oxygen. The inlet port l3 for the high pressure oxygen terminates in a lateral passage it which communicates with the passage 5 disposed in the longitudinal center of the torch head. The inlet port It for the fuel gas terminates in a chamber H from which a pinrality of minute passages 18 extend laterally of the torch head and communicate with the longitudinal passages 9-9 which lead into the mixing chamber 1. Each one of the passages l8 communicates with one of the longitudinal passages 9, so that each one of the longitudinal passages is in communication with the chamber I! through one passage 18. The inlet port l5 for the low pressure oxygen terminates in a chamber [9 formed in the rear end of the torch head, from which chamber I9 the passages 9-8 lead to the mixing chamber I. While the drawing shows only two such passages, it will be appreciated that the disclosure thereof is more or less of a schematic nature and is not intended to imply a structural limitation. It is important, however, that each one of the longitudinal passages 8 be supplied with fuel gas by but one passage l8 communicating with the chamber H.

In the above described arrangement of parts and passages, the initial mixture of the low pressure oxygen with the fuel gas takes place at each junction of passages 9 and I8. For the longitudinal passages 9 applicant uses drills not larger than number 54, and for the lateral passages It the drills are not larger than number 69. These respective drill sizes provide passages of 'such proportion that insufiicient oxygen is admitted through the passage 9 to render combustible the fuel gas supplied through the communicating passage 8, and the mixture of gases conducted to the chamber 1 is not combustible. The gases are used at the pressures at which they are commonly marketed for use in cutting and welding torches. By reason of the fact that the passages 9-9 which discharge into the chamber 7 are not aligned with the passages B which lead to the end of the tip, a positive mixing of the low pressure gases takes place within the chamber before these gases are discharged from the tip. At the point of discharge from the end of the tip, the mixed gases take enough oxygen from the atmosphere to become wholly combustible.

A further factor of safety in applicant's construction is the provision of the chambers ll and I! from which the low pressure gases are conducted through the passages 9 and I8. Each of these chambers provides an excess volume of gas which acts as a cushion to resist the force of minor explosions which may occur near the end of the tip. Acetylene gas by itself is not inflammable. and unless a considerable quantity of oxygen should leak back through the passages l8 into the chamber I1, the pocket of acetylene gas in the chamber ll would prevent the flame from striking back into the hose lines. a

A particular advantage of applicant's construction lies in the fact that the inlet for the high pressure oxygen is between the tip and the inlet for the low pressure gases. The flow of oxygen through the passages l6 and 5 tends to insulate the remainder of the torch head from the heat generated by the flame at the end of the tip, and so tends to keep the low pressure gases cool and prevents back-firing.

The torch head illustrated in the drawing is so constructed that the respective passages for the flow of gas therethrough are made available for cleaning purposes without removing the tip from the head or disconnecting the hose lines. The chamber IQ for the low pressure oxygen is closed by a tapered plug 20, and upon removal of the plug 20 cleaning elements can be inserted into the passages 99 to remove any obstructions therein. The chamber I1 for the fuel gas is closed by a tapered plug 2| threaded into one side of the boss or shank l2. Upon removal of the plug 2| the passages i8 may be cleaned by use of a suitable cleaning rod. In this connection it should be stated that at the time the extension 3 of the tip 2 is brazed into the socket I, the adjacent ends of the passages 9+9 are plugged with carbon to prevent the brazing solder from closing these passages. After the joint is brazed, the carbon is removed by running a cleaning rod through these passages from the opposite end of the torch head. 7

A torch employing the construction and embodying the principles of the hereinbefore described invention may be used with any one of the fuel gases commonly used for cutting and welding, and wherever applicant has used the term acetylene it is intended to embrace all such gases.

Having now described my invention and in what manner the same may be used, what I claim as new and desire to protect by Letters Patent is:

1. In a cutting torch, a torch head and a cutting tip therefor, said torch head being provided with an outer end socket, the tip being provided with an extension designed to extend into said socket, an annular chamber formed about the extension and disposed between the end of the torch head and the end of the tip, a ferrule disposed over the inner end of the tip and forming the outer wall of said chamber, a passage in said torch head opening into said socket, a passage in said tip extend ng through said extension and registering with said passage in the torch head, and passages in said torch head and said tip opening into and leading from said chamber, said extension being brazed into said socket to seal the flow of gas therethrough from said chamber.

2. A torch head for welding and cutting torches and a cutting tip therefor, a passage in said torch head, a passage in said tip registerin with the passage in the torch head, a brazed sea for sealing the juncture of said passages, a chamber disposed between the inner end of the tip and the end of the torch head, a ferrule over the inner end of the tip and forming the outer wall of said chamber, and brazed seals for securing said ferrule and sealing said chamber.

3. A torch head for welding and cutting torches, open at both ends, having a plurality of passages therethrough for conducting the separate gases to the tip, a chamber disposed in one end of said torch head, certain ones of said passages extending longitudinally through said torch head and communicating with said chamber, a second chamber-intermediate the ends of said torch head, certain ones of said passages extending transversely of said torch head and providing communication between said second chamber and said first named passages, and closure members-tor said chambers so constructed and arranged as to make said passages available for cleanina purposes without removing the tip gr disconnecting the supply lines irom said torch ead.

4. A torch head ior welding and cutting torches, open at both ends, raiity of passages therethrough for conductin the separate gases to the tip, a chamber disposed in one end of said torch head, certain ones of said passages extending longitudinally through said torch head and communicating with said and having a pluchamber, a closure member for said chamber so constructed and arranged as to make said passages available for cleaning purposes without removing the tip or disconnecting the supply lines from said torch head.

5. A cutting torch, comprising a torch head and a cutting tip therefor, a soclret in the outer end of said torch head, a central extension on the inner end of said tip, said extension being received in said socket and secured therein by means of a brazed seal, a chamber disposed between the inner end of the tip and the end of the torch head, and a ferrule disposed over the inner end of the tip and forming the outer wall of said chamber, one end of said ferrule being brazed to the tip and the other end being brazed to the torch head in such manner as to preclude leakage of gases from said chamber to the atmosphere.

SANFORD J. ERRE'IT. 

